a. Field of Invention
This invention pertains to a hybrid power drive system for motor vehicles including an electric motor as the primary mover, a battery and a generator for deriving electric power for the motor. These components are arranged to provide dynamic braking.
b. Description of the Prior Art
Today the overwhelming majority of motor vehicles on the road rely on internal combustion engines as the primary mover. However, because of numerous environmental and economic factors, these types of motor vehicles are becoming more and more unacceptable. All electric motor vehicles using storage batteries as the only power source are environmentally and economically more acceptable. Nonetheless, despite extensive experimentation in this area, no such vehicles were developed which could provide the acceleration or the operating range that is provided by vehicles with internal combustion. As an intermediate solution, hybrid motor vehicles have been suggested with drive systems consisting of an electric motor which is used as a prime mover, a storage battery, and a generator for charging the battery, and to augment the battery. Systems of this type are disclosed in U.S. Pat. Nos. 4,292,531; 4,438,342; 4,547,678; 3,888,325; 4,042,056; 4,099,589. However, none of these proposed systems are acceptable because they rely on complicated circuitry and are not capable of performing the required switching of power between various modes in a satisfactory manner.